1. Field of the Invention
The present invention relates to multi-type air conditioners, and more particularly, to a method for operating a multi-type air conditioner, in which an operation pattern of the outdoor unit is determined, efficiently.
2. Background of the Related Art
In general, the air conditioner is an appliance for cooling or heating spaces, such as living spaces, restaurants, and offices. At present, for effective cooling or heating of a space partitioned into many rooms, there has been ceaseless development of multi-type air conditioner for cooling or heating, or cooling and heating at the same time depending on operation conditions.
The multi-type air conditioner is in general provided with one outdoor unit having an outdoor heat exchanger for heat exchange between refrigerant and external air and a plurality of indoor units each connected to the outdoor unit. The operation pattern of the outdoor unit is dependent on operation patterns of indoor units which heat or cool the rooms.
A related art method for operating a multi-type air conditioner will be described, in which the operation pattern of the outdoor unit is dependent on the operation patterns of respective indoor units. First, when the indoor units only cool the rooms, the outdoor unit carries out a cooling operation, when the outdoor heat exchanger serves as a condenser. When the indoor units only heat the rooms, the outdoor unit carries out a heating operation, when the outdoor heat exchanger serves as an evaporator.
When some of the indoor units cool respective rooms, and, at the same time with this, rest of the indoor units heat respective rooms, a number of the indoor unit that cool the rooms and a number of the indoor unit that heat the rooms are compared, so that the outdoor unit carries out the cooling operation when the number of indoor units that cool the rooms is greater than the number of the indoor unit that heat the rooms, and vice versa.
However, the related art method for operating a multi-type air conditioner has the following problems. When the indoor units cool or heat the rooms respectively at the same time, there has been a problem of varying the operation pattern of the outdoor unit in the middle of operation because the operation pattern of the outdoor unit is determined simply based on comparison of numbers of indoor units that cool/heat rooms without determining a load required for operation of the indoor units, actually.
That is, even if the number of indoor unit that heat the rooms is greater than the number of indoor units that cool the rooms, if the indoor units require a heavier load in cooling, the outdoor unit requires to carry out cooling operation. However, in the related art operation method, the outdoor unit carries out heating operation, to cause to vary the operation pattern of the outdoor unit in the middle of the operation.
The variation of the operation pattern in the middle of operation causes waste of energy coming from a pressure loss, and failure in smooth operation of the cooling/heating.